bug 486992: post_upload.py errors aren't caught - use sys.exit(non-zero) when exceptions are caught in upload.py. r=ted

build/upload.py

@@ -224,5 +224,7 @@ if __name__ == '__main__':
                     verbose=True)
     except IOError, (strerror):
         print strerror
+        sys.exit(1)
     except Exception, (err):
         print err
+        sys.exit(2)